williamr@2: // Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@4: // under the terms of "Eclipse Public License v1.0"
williamr@2: // which accompanies this distribution, and is available
williamr@4: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // tcp_hdr.h - TCP protocol header structure
williamr@2: // Defines the basic classes for accessing the header structures within TCP packets.
williamr@2: //
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2:  @file tcp_hdr.h 
williamr@2:  @ingroup ip_packet_formats
williamr@2:  @publishedAll
williamr@2:  @released
williamr@2: */
williamr@2: 
williamr@2: #ifndef __TCP_HDR_H__
williamr@2: #define __TCP_HDR_H__
williamr@2: 
williamr@2: #include <e32std.h>
williamr@2: #include "in_hdr.h"
williamr@2: #include "sbque.h"
williamr@2: 
williamr@2: /**
williamr@2: * @addtogroup ip_packet_formats
williamr@2: * @{
williamr@2: */
williamr@2: 
williamr@2: //
williamr@2: // TInet6HeaderTCP
williamr@2: //
williamr@2: //	*NOTE*
williamr@2: //		TInet6HeaderTCP declares for maximum length TCP header
williamr@2: //		(64	bytes). A valid TCP packet can be shorter and failing
williamr@2: //		to map full 64 bytes from a packet is not an error condition.
williamr@2: //
williamr@2: 
williamr@2: /** @name TCP Header length constants
williamr@2: * @{
williamr@2: */
williamr@2: const TInt KTcpMinHeaderLength = 20;
williamr@2: const TInt KTcpMaxHeaderLength = 60;
williamr@2: const TInt KTcpMaxOptionLength = 40;
williamr@2: /** @} */
williamr@2: 
williamr@2: /** @name TCP control flags
williamr@2: * @{
williamr@2: */
williamr@2: const TUint8 KTcpCtlFIN = 1;
williamr@2: const TUint8 KTcpCtlSYN = 2;
williamr@2: const TUint8 KTcpCtlRST = 4;
williamr@2: const TUint8 KTcpCtlPSH = 8;
williamr@2: const TUint8 KTcpCtlACK = 16;
williamr@2: const TUint8 KTcpCtlURG = 32;
williamr@2: const TUint8 KTcpCtlECE = 0x40;
williamr@2: const TUint8 KTcpCtlCWR = 0x80;
williamr@2: /** @} */
williamr@2: 
williamr@2: /** @name TCP options
williamr@2: * @{
williamr@2: */
williamr@2: const TUint8 KTcpOptEnd		=  0;
williamr@2: const TUint8 KTcpOptNop		=  1;
williamr@2: const TUint8 KTcpOptMSS		=  2;
williamr@2: const TUint8 KTcpOptWScale	=  3;
williamr@2: const TUint8 KTcpOptSackOk	=  4;
williamr@2: const TUint8 KTcpOptSack	=  5;
williamr@2: const TUint8 KTcpOptTimeStamps  =  8;
williamr@2: const TUint8 KTcpOptCount	=  9;
williamr@2: 
williamr@2: const TUint8 KTcpOptMinLen[] =  {1,  1,  4,  3,  2,  6,  2,  2, 10};
williamr@2: const TUint8 KTcpOptMaxLen[] =  {1,  1,  4,  3,  2, 36, 40, 40, 10};
williamr@2: const TUint32 KTcpOptAlignFlag = 0x00000001;
williamr@2: /** @} */
williamr@2: 
williamr@2: 
williamr@2: class TTcpOptions
williamr@2: /** TCP Options Header.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public:
williamr@2:   	inline TTcpOptions()			      { Init(); }
williamr@2:   	IMPORT_C void Init();
williamr@2:   	IMPORT_C TInt Length() const;
williamr@2:   	inline TBool Error() const		  { return iError; }
williamr@2:   	inline void ClearError()		      { iError = EFalse; }
williamr@2: 
williamr@2:   	inline TInt MSS() const		      { return iMSS; }
williamr@2:   	inline void SetMSS(TInt aMSS)		  { iMSS = aMSS; }
williamr@2:   	inline void ClearMSS()		      { iMSS = -1; }
williamr@2: 
williamr@2:   	inline TBool TimeStamps() const	  { return iTimeStamps; }
williamr@2:   	inline TBool TimeStamps(TUint32& aTsVal, TUint32& aTsEcr) const
williamr@2:     	{
williamr@2:       	aTsVal = iTsVal;
williamr@2:       	aTsEcr = iTsEcr;
williamr@2:       	return iTimeStamps;
williamr@2:     	}
williamr@2:   	inline void SetTimeStamps(TUint32 aTsVal, TUint32 aTsEcr)
williamr@2:     	{
williamr@2:       	iTsVal = aTsVal;
williamr@2:       	iTsEcr = aTsEcr;
williamr@2:       	iTimeStamps = ETrue;
williamr@2:     	}
williamr@2:   	inline void ClearTimeStamps()		  { iTimeStamps = EFalse; }
williamr@2: 
williamr@2:   	inline TBool SackOk() const		  { return iSackOk; }
williamr@2:   	inline void SetSackOk()		      { iSackOk = ETrue; }
williamr@2:   	inline void ClearSackOk()		      { iSackOk = EFalse; }
williamr@2:   	inline void SuppressSack(TBool aBool=ETrue) { iSuppressSack = aBool; }
williamr@2:   	inline SequenceBlockQueue& SackBlocks()     { return iBlocks; }
williamr@2: 
williamr@2:   	inline TInt Unknown() const		  { return iUnknown; }
williamr@2:   	inline void ClearUnknown()		  { iUnknown = 0; }
williamr@2:   
williamr@4:   	// Query window scale option from TCP header options.
williamr@4:   	// Wscale == 1 means scale factor 1, i.e. shift count of 0 is used in TCP option.
williamr@4:   	// Wscale == 0 means that wscale option is not used in TCP header.
williamr@2:   	inline TUint WindowScale() const		{ return iWscale; }
williamr@2: 
williamr@2:   	inline void SetWindowScale(TUint8 aWscale)	{ iWscale = aWscale; }
williamr@2:   	
williamr@2:   	/**
williamr@2:   	If set, each option will be aligned to 32-bit longword boundaries with Nop padding.
williamr@2:   	By default the Nop padding is not applied.
williamr@2:   	
williamr@2:   	@param aAlignNop	ETrue if option alignment should be applied. 
williamr@2: 	*/
williamr@2:   	inline void SetAlignOpt(TBool aAlignOpt) 
williamr@2:   		{ 
williamr@2:   		if(aAlignOpt) 
williamr@2:   			iFlags |= KTcpOptAlignFlag; 
williamr@2:   		else 
williamr@2:   			iFlags &= ~KTcpOptAlignFlag;
williamr@2:   		}
williamr@2: 
williamr@2: private:
williamr@2:   	friend class TInet6HeaderTCP;
williamr@2: 
williamr@2:   	IMPORT_C TBool ProcessOptions(const TUint8 *aPtr, TUint aLen);
williamr@2:   	IMPORT_C TUint OutputOptions(TUint8 *aPtr, TUint aMaxLen);
williamr@2:   	
williamr@2:   	void CheckOptAlignment(TUint8* aPtr, TUint& aI, TUint aNumBytes);
williamr@2:   	
williamr@2:   	inline TInt AlignedLength(TInt aLength) const
williamr@2:   	/**
williamr@2:   	Calculate the actual space requirement for option with given length.
williamr@2:   	
williamr@2:   	Takes optional 32-bit alignment into account.
williamr@2:   	*/
williamr@2:   		{ if (iFlags & KTcpOptAlignFlag) return (aLength + 3) & ~3; else return aLength; }
williamr@2: 
williamr@2:   	TInt	              iMSS;
williamr@2:   	TInt	              iUnknown;
williamr@2:   	TUint32             iTsVal;
williamr@2:   	TUint32             iTsEcr;
williamr@2:   	SequenceBlockQueue  iBlocks;
williamr@2:   	TBool	              iError;
williamr@2:   	TBool	              iTimeStamps;
williamr@2:   	TBool	              iSackOk;
williamr@2:   	TBool               iSuppressSack;
williamr@4:   	TUint				iWscale;	//< Window scale option [RFC 1323].
williamr@4:   	TUint32				iFlags;	//< ETrue if options are to be aligned.
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: class TInet6HeaderTCP
williamr@2: /**  TCP segment header.
williamr@2: @verbatim
williamr@2: Extract from RFC-793
williamr@2: 
williamr@2:     0                   1                   2                   3
williamr@2:     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |          Source Port          |       Destination Port        |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |                        Sequence Number                        |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |                    Acknowledgment Number                      |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |  Data |           |U|A|P|R|S|F|                               |
williamr@2:    | Offset| Reserved  |R|C|S|S|Y|I|            Window             |
williamr@2:    |       |           |G|K|H|T|N|N|                               |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |           Checksum            |         Urgent Pointer        |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |                    Options                    |    Padding    |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2:    |                             data                              |
williamr@2:    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
williamr@2: @endverbatim
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public:
williamr@2: 	//
williamr@2: 	// Basic
williamr@2: 	//
williamr@2: 	inline static TInt MinHeaderLength() {return KTcpMinHeaderLength; }
williamr@2: 	inline static TInt MaxHeaderLength() {return KTcpMaxHeaderLength; }
williamr@2: 	inline TUint8 *EndPtr() {return i + HeaderLength();}
williamr@2: 	//
williamr@2: 	// Access, Get TCP field values from the packet
williamr@2: 	//
williamr@2: 	inline TUint SrcPort() const
williamr@2: 		{
williamr@2: 		return (i[0] << 8) + i[1];
williamr@2: 		}
williamr@2: 	inline TUint DstPort() const
williamr@2: 		{
williamr@2: 		return (i[2] << 8) + i[3];
williamr@2: 		}
williamr@2: 	inline TTcpSeqNum Sequence() const
williamr@2: 		{
williamr@2: 		return (i[4] << 24) | (i[5] << 16) | (i[6] << 8) | i[7];
williamr@2: 		}
williamr@2: 	inline TTcpSeqNum Acknowledgment() const
williamr@2: 		{
williamr@2: 		return (i[8] << 24) | (i[9] << 16) | (i[10] << 8) | i[11];
williamr@2: 		}
williamr@2: 	inline TInt HeaderLength() const
williamr@2: 		{
williamr@2: 		// Return TCP Header Length in bytes (including options and padding)
williamr@2: 		return (i[12] >> 2) & (0xF << 2);
williamr@2: 		}
williamr@2: 	//
williamr@2: 	// A testing method for each individual Control Bit is provided
williamr@2: 	// (It remains to be seen whether this is useful or not). Note
williamr@2: 	// also that the result of the AND is returned, not 0 and 1.
williamr@2: 	//
williamr@2: 	inline TInt FIN() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlFIN;
williamr@2: 		}
williamr@2: 	inline TInt SYN() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlSYN;
williamr@2: 		}
williamr@2: 	inline TInt RST() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlRST;
williamr@2: 		}
williamr@2: 	inline TInt PSH() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlPSH;
williamr@2: 		}
williamr@2: 	inline TInt ACK() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlACK;
williamr@2: 		}
williamr@2: 	inline TInt URG() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlURG;
williamr@2: 		}
williamr@2: 
williamr@4: 	// ECN Echo flag [RFC 3168].
williamr@2: 	inline TInt ECE() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlECE;
williamr@2: 		}
williamr@2: 
williamr@4: 	// ECN: Congestion Window Reduced [RFC 3168].
williamr@2: 	inline TInt CWR() const
williamr@2: 		{
williamr@2: 		return i[13] & KTcpCtlCWR;
williamr@2: 		}	
williamr@2: 		
williamr@2: 	// A method to access all of the above as is. Note that this
williamr@2: 	// also returns the reserved unspecified bits. Value can be
williamr@2: 	// non-zero, even if none of the above is set. However, it only
williamr@2: 	// returns unspecified bits from the 13th byte, not any from 12th!
williamr@2: 	inline TUint8 Control() const
williamr@2: 		{
williamr@2: 		return i[13];
williamr@2: 		}
williamr@2: 	//
williamr@2: 	inline TUint Window() const
williamr@2: 		{
williamr@2: 		return (i[14] << 8) + i[15];
williamr@2: 		}
williamr@2: 	inline TUint Checksum() const
williamr@2: 		{
williamr@2: 		// Checksum is used in network byte order
williamr@2: 		return *((TUint16 *)&i[16]);
williamr@2: 		}
williamr@2: 	inline TUint Urgent() const
williamr@2: 		{
williamr@2: 		return (i[18] << 8) + i[19];
williamr@2: 		}
williamr@2: 	inline TBool Options(TTcpOptions& aOptions) const
williamr@2: 		{
williamr@2: 		return aOptions.ProcessOptions(i + KTcpMinHeaderLength, HeaderLength() - KTcpMinHeaderLength);
williamr@2: 		}
williamr@2: 	//Backwards compatibility, mainly for IPRotor.
williamr@2: 	inline TPtr8 Options() const
williamr@2: 		{
williamr@2: 		TInt len = HeaderLength() - 20;
williamr@2: 		return TPtr8((TUint8 *)&i[20], len, len);
williamr@2: 		}
williamr@2: 
williamr@2: 	//
williamr@2: 	// Build, Set TCP field value to the packet
williamr@2: 	//
williamr@2: 	inline void SetSrcPort(TUint aPort)
williamr@2: 		{
williamr@2: 		i[0] = (TUint8)(aPort >> 8);
williamr@2: 		i[1] = (TUint8)aPort;
williamr@2: 		}
williamr@2: 	inline void SetDstPort(TUint aPort)
williamr@2: 		{
williamr@2: 		i[2] = (TUint8)(aPort >> 8);
williamr@2: 		i[3] = (TUint8)aPort;
williamr@2: 		}
williamr@2: 	inline void SetSequence(TTcpSeqNum aSeq)
williamr@2: 		{
williamr@2: 		i[7] = (TUint8)aSeq.Uint32();
williamr@2: 		i[6] = (TUint8)(aSeq.Uint32() >> 8);
williamr@2: 		i[5] = (TUint8)(aSeq.Uint32() >> 16);
williamr@2: 		i[4] = (TUint8)(aSeq.Uint32() >> 24);
williamr@2: 		}
williamr@2: 	inline void SetAcknowledgment(TTcpSeqNum aAck)
williamr@2: 		{
williamr@2: 		i[11] = (TUint8)aAck.Uint32();
williamr@2: 		i[10] = (TUint8)(aAck.Uint32() >> 8);
williamr@2: 		i[9] = (TUint8)(aAck.Uint32() >> 16);
williamr@2: 		i[8] = (TUint8)(aAck.Uint32() >> 24);
williamr@2: 		}
williamr@2: 	inline void SetHeaderLength(TUint aLength)
williamr@2: 		{
williamr@2: 		// *NOTE* A very low level function, no sanity
williamr@2: 		// checks on value, no rounding up. Value is just
williamr@2: 		// truncated and shifted to the proper position
williamr@2: 		// (all other bits of this byte should always
williamr@2: 		// be zero!)
williamr@2: 		i[12] = (TUint8)((aLength >> 2) <<4);
williamr@2: 		}
williamr@2: 	//
williamr@2: 	// A set method for each individual Control Bit is provided
williamr@2: 	// (It remains to be seen whether this is sensible or not).
williamr@2: 	//
williamr@2: 	inline void SetFIN()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlFIN;
williamr@2: 		}
williamr@2: 	inline void SetSYN()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlSYN;
williamr@2: 		}
williamr@2: 	inline void SetRST()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlRST;
williamr@2: 		}
williamr@2: 	inline void SetPSH()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlPSH;
williamr@2: 		}
williamr@2: 	inline void SetACK()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlACK;
williamr@2: 		}
williamr@2: 	inline void SetURG()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlURG;
williamr@2: 		}
williamr@2: 		
williamr@4: 	// Set ECN Echo flag [RFC 3168].
williamr@2: 	inline void SetECE()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlECE;
williamr@2: 		}
williamr@2: 		
williamr@4: 	// Set ECN Congestion Window Reduced [RFC 3168].
williamr@2: 	inline void SetCWR()
williamr@2: 		{
williamr@2: 		i[13] |= KTcpCtlCWR;
williamr@2: 		}
williamr@2: 		
williamr@2: 	//
williamr@2: 	// Note: does not touch the unused control bits at 12th byte!!!
williamr@2: 	//
williamr@2: 	inline void SetControl(TUint8 aFlags)
williamr@2: 		{
williamr@2: 		i[13] = aFlags;
williamr@2: 		}
williamr@2: 	//
williamr@2: 	inline void SetWindow(TUint aWin)
williamr@2: 		{
williamr@2: 		i[15] = (TUint8)aWin;
williamr@2: 		i[14] = (TUint8)(aWin >> 8);
williamr@2: 		}
williamr@2: 	inline void SetChecksum(TUint aSum)
williamr@2: 		{
williamr@2: 		// Checksum is used in network byte order
williamr@2: 		*((TUint16 *)&i[16]) = (TUint16)aSum;
williamr@2: 		}
williamr@2: 	inline void SetUrgent(TUint aOff)
williamr@2: 		{
williamr@2: 		i[19] = (TUint8)aOff;
williamr@2: 		i[18] = (TUint8)(aOff >> 8);
williamr@2: 		}
williamr@2: 	inline TInt SetOptions(TTcpOptions& aOptions)
williamr@2: 		{
williamr@2: 		TInt optLen = aOptions.OutputOptions(i + KTcpMinHeaderLength, KTcpMaxOptionLength);
williamr@2: 		SetHeaderLength(KTcpMinHeaderLength + optLen);
williamr@2: 		return optLen;
williamr@2: 		}
williamr@2: 
williamr@2: protected:
williamr@2: 	TUint8 i[KTcpMaxHeaderLength];
williamr@2: 	};
williamr@2: 
williamr@2: /** @} */
williamr@2: #endif